I partly agree with Thomas Nagel, that my consciousness is “what it is like” to be the thing that I am. But I don’t see that as incompatible with materialism/reductionism/physicalism. Specifically, my consciousness is what it’s like to be a certain type of complex physical object as it interacts with its environment. Far from dividing the world into conscious and unconscious things, I would argue that there is also “something that it is like” to be a rock, analogous to what it is like to be a human.
My experience of consciousness is the experience of having a body and brain with a particular architecture. Our bodies are configured such that our interactions with our environment set off chemical and electrical cascades along our nervous system and into our brains. Our brains, in turn, are a network of similar channels, with endless loops of similar cascades. Cascades from outside of our brains change the cascades inside our brains, and in doing so they insert information from our environment. But because the cascades in our brains are looping, they are also incorporating information about the state and operation of the brain. Our self-awareness is the process of different parts of our brains physically sensing other parts of our brains, and indeed of parts of our bodies physically sensing other parts of our bodies, e.g. our eyes perceiving the goosebumps on the back of our hands. We are self-aware because we are physically configured to react to our own physical states.
That does not mean that there isn’t something-that-it’s-like to be an object that isn’t configured that way. When a rock collides with my hand, that physical interaction changes my body. It also changes the rock: vibrations propagates through the material, its temperature changes, and the bonds between its constituent molecules may be affected, possibly catalyzing chemical changes. These are the rock’s ‘experiences’. Where my experiences include a memory of another time I hit a rock (i.e. a series of chemical cascade similar those triggered by the immediate experience of hitting a rock), the rock’s experiences are simpler: the energy dissipates, information about previous interactions has little effect, and the information about this interaction is almost entirely lost as heat.
This isn’t a difference in kind, it’s a difference in degree, in complexity, in the quantity of information processed. The rock processes some information, and our brains process much more. But all physical systems process some information, and the processing of information is “what it’s like to be” each system.
